U.S. patent number 8,727,969 [Application Number 12/187,246] was granted by the patent office on 2014-05-20 for endoscope.
This patent grant is currently assigned to Lighthouse Imaging, LLC. The grantee listed for this patent is Dennis C. Leiner. Invention is credited to Dennis C. Leiner.
United States Patent |
8,727,969 |
Leiner |
May 20, 2014 |
Endoscope
Abstract
An endoscope includes an outer tube having a sharpened distal
end and a retractable sleeve slidably disposed in the outer tube.
An image conduit is attached to the distal end of the retractable
sleeve for imaging any object in contact with the distal tip of the
image conduit.
Inventors: |
Leiner; Dennis C. (Cape
Elizabeth, ME) |
Applicant: |
Name |
City |
State |
Country |
Type |
Leiner; Dennis C. |
Cape Elizabeth |
ME |
US |
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Assignee: |
Lighthouse Imaging, LLC
(Windham, ME)
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Family
ID: |
40342025 |
Appl.
No.: |
12/187,246 |
Filed: |
August 6, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20090043167 A1 |
Feb 12, 2009 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60954114 |
Aug 6, 2007 |
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Current U.S.
Class: |
600/114; 600/129;
600/156; 600/182 |
Current CPC
Class: |
A61B
17/12104 (20130101); G02B 27/0006 (20130101); G02B
1/10 (20130101); A61M 13/003 (20130101); A61B
1/00165 (20130101); A61B 90/361 (20160201); A61B
17/3474 (20130101); G02B 23/26 (20130101); A61B
1/00119 (20130101); A61B 1/3132 (20130101); A61M
25/00 (20130101) |
Current International
Class: |
A61B
1/00 (20060101); A61B 1/04 (20060101); A61B
1/12 (20060101); A61B 1/06 (20060101) |
Field of
Search: |
;600/114,121-125,129,175,176,132,136,160,172,180,108,171,177,182,104,115-116,120,153,156,157,158 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Nia; Alireza
Attorney, Agent or Firm: Haszko; Dennis R.
Claims
What is claimed is:
1. An endoscope comprising: an outer tube having a sharpened distal
end; a retractable sleeve slidably disposed in said outer tube,
said retractable sleeve having a sidewall and an insufflation
channel formed in said sidewall; an image guide disposed in said
retractable sleeve, said image guide being movable in a sliding
manner between an inserted position within said retractable sleeve
and a removed position therefrom, said image guide restricting gas
flow to said insufflation channel while said image guide is in the
inserted position; a hollow interior formed within said retractable
sleeve while said image guide is in the removed position, said
hollow interior enabling gas flow to said insufflation channel; and
an image conduit fixed in the distal end of said retractable
sleeve, the image conduit having a proximal and distal end, wherein
the image conduit comprises image fiber having multiple optical
fibers fused together with a one-to-one correspondence in the
optical fibers' position at the proximal and distal ends of the
optical fibers and wherein the image conduit does not function as a
lens, and wherein said image conduit transfers an image of an
object in contact with a distal tip of the image conduit through
said image guide while in the inserted position to the proximal end
of said image guide.
2. The endoscope of claim 1 wherein the distal tip of said image
conduit extends beyond said distal end of said retractable
sleeve.
3. The endoscope of claim 1, wherein the distal end of said image
guide is positioned against said image conduit and the proximal end
of said image guide extends beyond the proximal end of said
retractable sleeve.
4. The endoscope of claim 1 wherein said image fiber is enclosed in
a protective sleeve.
5. The endoscope of claim 3 wherein said image guide is removably
mounted in said retractable sleeve.
6. The endoscope of claim 3 further comprising an index matching
material disposed between said distal end of said image guide and
said image conduit.
7. The endoscope of claim 3 further comprising an optical system
positioned adjacent to the proximal end of said image guide.
8. The endoscope of claim 7 wherein said optical system includes a
beamsplitter in contact with the proximal end of said image guide
and a lens located adjacent to said beamsplitter.
9. The endoscope of claim 8 wherein said lens is an ocular.
10. The endoscope of claim 8 wherein said lens is a video relay
lens.
11. The endoscope of claim 8 wherein said optical system further
includes a light source arranged to direct light into said
beamsplitter and then through said image guide.
12. The endoscope of claim 7 wherein said optical system further
includes means for determining when said image conduit enters a
body cavity.
13. The endoscope of claim 1 further comprising means for
connecting the interior of said retractable sleeve to a gas
source.
14. The endoscope of claim 13 wherein said insufflation channel is
formed adjacent to said image conduit.
15. The endoscope of claim 12 wherein said means for determining
includes means for detecting a change in the intensity and/or color
of an image transmitted by said image conduit.
16. The endoscope of claim 15 further comprising means for
producing an output signal in response to said means for detecting
a change in the intensity and/or color of an image transmitted by
said image conduit.
17. The endoscope of claim 1 wherein said retractable sleeve is
spring-loaded within said outer tube.
18. The endoscope of claim 1, wherein the distal tip of the image
conduit has a conical tip for separating soft tissue when making
the incision.
19. The endoscope of claim 1, wherein the distal tip of the image
conduit has a cutting edge.
20. The endoscope of claim 5, wherein the insufflation channel does
not overlap the image conduit.
21. An endoscope comprising: a sleeve including a proximal and
distal end; an insufflation channel located within said sleeve near
said distal end; an image guide mounted in said sleeve and movable
between a first position restricting said insufflation channel from
gas flow through said sleeve and a second position allowing gas
flow through said sleeve to said insufflation channel; an image
conduit fixed in said distal end of said sleeve, said image conduit
transferring, in a return path through said image guide while in
said first position, an image of an object in contact with a distal
surface of said image conduit to said proximal end while also
transmitting light to said distal surface in an initial path
opposite to said return path for illumination of said object; and
an index matching material disposed between an interface of said
image guide and said image conduit.
22. The endoscope of claim 21 further comprising an optical system
including a beamsplitter in contact with the proximal end of said
image guide, a lens located adjacent to said beamsplitter and
oriented in alignment with said return path, and a light source
arranged to direct light into said beamsplitter and then through
said image guide.
23. An endoscope comprising: an outer tube having a sharpened
distal end; a retractable sleeve slidably disposed and
spring-loaded within said outer tube, said retractable sleeve
including a proximal and distal end; an insufflation channel
located within said retractable sleeve near said distal end; an
image guide mounted in said retractable sleeve and movable between
a first position restricting said insufflation channel from gas
flow through said retractable sleeve and a second position allowing
gas flow through said retractable sleeve to said insufflation
channel; an image conduit fixed to said distal end of said
retractable sleeve, said image conduit actuating said retractable
sleeve so as to expose said sharpened distal end of said outer tube
upon contact of an object with a distal surface of said image
conduit, said imagine conduit being fixed in said distal end of
said retractable sleeve, said image conduit transferring, in a
return path through said image guide, an image of an object in
contact with a distal surface of said image conduit to said
proximal end while also transmitting light to said distal surface
in an initial path opposite to said return path for illumination of
said object; and an index matching material disposed between an
interface of said image guide and said image conduit.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent
Application No. 60/954,114, filed Aug. 6, 2007.
BACKGROUND OF THE INVENTION
This invention relates generally to devices and techniques for
performing endoscopic surgery.
The use of endoscopes enables minimally invasive surgical
procedures to be performed in normally closed body cavities, such
as the abdominal cavity. (Endoscopy in the abdominal cavity is
referred to as laparoscopy.) The abdominal cavity typically needs
to be insufflated prior to performing a laparoscopic procedure to
create space between the abdominal wall and organs and arteries in
the abdominal cavity. This space permits the various surgical
devices to be safely inserted and used. Many other body cavities
similarly need to be insufflated to perform an endoscopic
procedure.
Verres needles are well known to surgeons for producing an initial
entry incision during laparoscopic surgery and injecting gas into
the abdominal cavity to insufflate the cavity. A Verres needle
generally includes a hollow tube having a sharpened tip and means
for injecting insufflation gas through the tube. The first surgical
device typically inserted after the Verres needle is the
laparoscope. Means for visualizing the insertion of the laparoscope
are well known and are manufactured by companies such as Ethicon
and Covidien.
A problem inherent with conventional Verres needles is that it has
been difficult to precisely control the location of the needle tip
while making the initial incision. The positioning of the needle
tip during the initial incision is critical because insufflation
has not yet been performed at this point in the procedure meaning
that the patient's arteries and organs are in close proximity to
the inside wall of the body cavity. The procedure can be
particularly dangerous to the patient because if the needle tip is
inserted too deeply, there is a risk of puncturing an artery, such
as the aorta, or an internal organ. On the other hand, the body
cavity cannot be insufflated if the needle tip is not fully
inserted thorough the inside wall and into the body cavity.
Various attempts have been made to overcome the difficulty of
positioning the needle tip during the initial incision. For
example, U.S. Pat. No. 4,254,762, issued Mar. 10, 1981 to Yoon,
describes a system including an "endoscope means" 10 and a "trocar
means" 38 encircling the endoscope means. The trocar means has a
sharpened end for puncturing the wall of a body cavity. The
endoscope means permits the surgeon to visually monitor the
puncture of a body cavity. The endoscope means is also
spring-biased in the trocar means. When the sharpened end of the
trocar means pierces the wall of a body cavity, the spring bias
drives the endoscope means into contact with an abutment on the
trocar means, thereby providing an audible signal of the completion
of the puncture. Yoon does not specifically describe an endoscope
designed to image tissue in contact with the tip of the endoscope.
Conventional endoscopes are typically designed to image objects
removed from the tip of the endoscope.
SUMMARY OF THE INVENTION
One embodiment of the present invention includes an endoscope
comprising an outer tube having a sharpened distal end and a
retractable sleeve slidably disposed in the outer tube. An image
conduit is attached to the distal end of the retractable sleeve for
imaging any object in contact with the distal tip of the image
conduit.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of an endoscope.
FIG. 2 is a cross-sectional view of the distal end of the endoscope
of FIG. 1, with its retractable sleeve in an extended position.
FIG. 3 is a cross-sectional view of the distal end of the endoscope
of FIG. 1, with its retractable sleeve in a retracted position.
FIG. 4 is a cross-sectional view of the distal end of the endoscope
of FIG. 1, with its image guide removed.
FIG. 5 is a cross-sectional view of an end assembly of the
endoscope of FIG. 1.
FIG. 6 is a cross-sectional view of an end assembly of the
endoscope of FIG. 1, with its image guide removed.
FIG. 7 is a cross-sectional view of an optical system for the
endoscope of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings wherein identical reference numerals
denote the same elements throughout the various views, FIG. 1 shows
one embodiment of an endoscope 10 that can be used for initiating
laparoscopic surgery. The endoscope 10 includes means for making an
initial incision in body tissue through which the device can be
inserted into a body cavity. As used herein, the term "body cavity"
refers to any space (typically fluid filled) in the body of a human
or other animal. This includes, but is not limited to, the
abdominal cavity, the thoracic cavity, and the subarachnoid space
of the spinal column. In the illustrated embodiment, the endoscope
10 is an insufflation endoscope that includes means for
insufflating the body cavity. The endoscope 10 also includes means
for imaging anatomical regions in contact with the tip of the
endoscope 10 (and thus in close proximity to the cutting means),
thereby permitting safer initial entry into the body cavity. It
should be noted that while the endoscope 10 is particularly useful
in laparoscopic procedures, it is not so limited, and can be used
in a variety of other procedures including lumbar punctures (e.g.,
spinal taps). It is also noted that as used herein, the term
"proximal" refers to the end or portion of a structural element
that is normally oriented or positioned outside of, or away from,
the patient, while the term "distal" refers to the end or portion
of a structural element that is normally oriented or positioned
inside of, or nearest to, the patient.
The endoscope 10 includes an outer tube 12 having a sharpened
distal end 14 and an end assembly 16 attached to the distal end
thereof. A retractable sleeve 18 is slidably disposed in the outer
tube 12; that is, the retractable sleeve 18 is coaxially situated
inside the hollow interior of the outer tube 12 and is capable of
sliding or moving longitudinally with respect to the outer tube 12.
A shaped image conduit 20 is mounted to the distal end of the
retractable sleeve 18. The end assembly 16 includes a handle
portion 22 and a connector 24 for connecting the insufflation
endoscope 10 to a source of insufflation gas. An optical system
(not shown in FIG. 1, but described below) is connected to the end
assembly 16 to enable viewing of the images produced by the
insufflation endoscope 10.
Referring to FIGS. 2 and 3, the sharpened distal end 14 of the
outer tube 12 is configured into a pointed tip that is sufficiently
sharp to make an incision through tissue and into a body cavity.
The retractable sleeve 18 is a flat-ended tube having an open
distal end. The image conduit 20 is fixed in the distal end of the
retractable sleeve 18, with a portion of the image conduit 20
extending beyond the distal end of the retractable sleeve 18. This
protruding portion defines a distal tip 26 of the image conduit 20.
The retractable sleeve 18 is spring-loaded in such a manner that
the distal end of the sleeve 18 is normally biased to protrude
beyond the distal end 14 of the outer tube 12, as shown in FIG. 2.
Thus, when the endoscope 10 is not in use, the sharpened distal end
14 is largely concealed to reduce the chance of the sharpened
distal end 14 causing an injury. However, when the distal tip 26 is
pressed against body tissue, the resulting force exerted thereon
causes the retractable sleeve 18 to be retracted into the outer
tube 12, as shown in FIG. 3. This exposes the sharpened distal end
14 to enable an incision to be made in the tissue. At least one
insufflation channel 28 is formed through the sidewall of the
retractable sleeve 18, adjacent to, but not overlapping, the image
conduit 20.
The shaped image conduit 20 can be constructed from image fiber,
available from several companies, such as Sumitomo Electric
Industries, Ltd. and Fujikura America, Inc. Image fiber, which is
well known for use in constructing fiberoptic endoscopes, generally
comprises multiple optical fibers (typically made from silica,
glass, plastic or the like) fused together with a one-to-one
correspondence in their positions at the distal and proximal ends.
The image conduit 20 transfers an image of an object in contact
with the distal tip 26 to its proximal end. Any object in contact
with the distal tip 26 will be in sharp focus. However, objects
removed from the distal tip 26 generally will not be in sharp
focus. The image conduit 20 does not function as a lens; it is not
designed to image surfaces not in contact with the distal tip 26.
In a conventional endoscope, this feature would be detrimental
because it is normally desired to obtain a sharp image from objects
removed from the tip of the endoscope. However, only the image at
the distal tip 26 is of interest in the present invention. Because
tissue is translucent or opaque, a conventional endoscope with a
distal lens focusing on objects removed from the tip could not
obtain a useful image.
In the illustrated embodiment, the image conduit 20 is shaped so
that the distal tip 26 defines a rounded, blunt surface. This is
similar to conventional Verres needles, so there is little
difference in appearance. The surgeon is therefore able to use the
insufflation endoscope 10 in the same manner as a conventional
Verres needle, except the imaging means of the endoscope 10 allows
the surgeon to visually monitor the cutting of the incision. The
shaped image conduit 20 can have many other shapes as well. For
example, the image conduit 20 could have a flat distal tip, which
would likely be less expensive to manufacture, or the image conduit
20 could have a conical distal tip, which would be helpful in
separating soft tissue when making the incision. Furthermore, the
distal tip 26 could be sharpened, such as into a chisel shape, so
as to form a cutting edge. This would eliminate any need for the
outer tube 12 as a cutting implement.
An image guide 30 is removably mounted in the retractable sleeve 18
for transmitting the image formed at the proximal end of the shaped
image conduit 20 to the proximal end of the endoscope 10. In one
embodiment, the image guide 30 comprises a second image conduit 32
constructed from image fiber and enclosed in a protective sleeve
34. The protective sleeve 34 is open at both ends so that light can
be transmitted through the length of the image guide 30. The distal
end of the image guide 30 is positioned against the proximal end of
the image conduit 20, and the image guide 30 extends through the
remaining length of the retractable sleeve 18 such that its
proximal end extends beyond the proximal end of the retractable
sleeve 18. An index matching material 36 such as a gel or liquid is
applied between the distal end of the image guide 30 and the
proximal end of the image conduit 20 to reduce Fresnel reflections
from these two surfaces.
The image guide 30 is mounted in the retractable sleeve 18 in such
a manner that permits it to be removed therefrom. For instance, the
outer surface of the protective sleeve 34 can be such that the
image guide 30 fits snugly inside the retractable sleeve 18,
thereby producing a friction fit between these two components.
Thus, the image guide 30 will generally be retained in the
retractable sleeve 18 and thus move with the sleeve 18 when it
slides within the outer tube 12. However, the image guide 30 can
also be removed from the retractable sleeve 18 by pulling on its
distal end. When the image guide 30 is removed, as shown in FIG. 4,
the hollow interior of the retractable sleeve 18 is open. Thus, gas
injected into the retractable sleeve 18 (depicted by arrow A) will
flow out through the insufflation channel 28 (arrow B). Thus,
insufflations of a body cavity can take place when the distal end
of the endoscope 10 is positioned within the body cavity.
Turning to FIG. 5, the end assembly 16 includes a body member 38
having a central through bore 40 formed therein. The handle portion
22 is integrally formed on the distal end of the body member 38,
and the connector 24 is located between the handle portion 22 and
the proximal end of the body member 38. The body member 38 is
fixedly attached to the proximal end of the outer tube 12, which is
located in the distal end of the bore 40. As mentioned above, the
retractable sleeve 18 is spring-loaded within the outer tube 12.
FIG. 5 shows one possible arrangement for this. The bore 40
includes an enlarged section 42 located intermediate the two ends
of the bore 40. The distal end of the enlarged section 42, located
adjacent to the proximal end of the outer tube 12, defines a distal
shoulder or abutment 44, and the proximal end of the enlarged
section 42 defines a proximal shoulder or abutment 46. The proximal
end of the retractable sleeve 18 extends into the enlarged section
42. A ring 48 is formed on or fixed to the proximal end of the
retractable sleeve 18 and is located in the enlarged section 42.
The ring 48, which has substantially the same cross-sectional shape
as the enlarged section 42, is capable of sliding within the
enlarged section 42 as the retractable sleeve 18 moves
back-and-forth within the outer tube 12. A compression spring 50 is
located in the enlarged section 42, extending between the ring 48
and the proximal abutment 46. The spring 50 thus biases the ring 48
into engagement with the distal abutment 44, as shown in FIG. 5,
which in turn biases the retractable sleeve 18 distally. A
sufficient force exerted on the distal tip 26 will cause the
retractable sleeve 18 and the ring 48 to move proximally,
compressing the spring 50.
The image guide 30 extends through the bore 40 and beyond the
proximal end of the body member 38. A knob 52 is fixed to the
portion of the image guide 30 that extends beyond the proximal end
of the body member 38. Specifically, the image guide proximal end
is fixedly received within a central bore 54 formed in the knob 52.
The bore 54 is open at the proximal end of the knob 52 so that the
image guide 30 is able to optically interface with an optical
system. A counter bore 56 formed in the distal end of the knob 52
fits snugly over the proximal end of the body member 38 so as to be
removably retained thereon. The knob 52 and image guide 30 can be
removed from the endoscope 10 by pulling on the knob 52 while
grasping the handle portion 22.
The connector 24 for connecting the insufflation endoscope 10 to a
source of insufflation gas provides the connector 24 includes a
valve 58 that, when the image guide 30 is removed as shown in FIG.
6, can be operated to allow gas from the gas source to flow into
the bore 40. The gas flows from the bore 40 into the hollow
interior of the retractable sleeve 18, which is in fluid
communication with the bore 40. The gas is then injected into the
body cavity through the insufflation channel 28 (as shown in FIG.
4), thereby insufflating the body cavity.
The endoscope 10 can include an optical system for viewing the
image produced at the proximal end of the image guide 30. An ocular
may be used to magnify the image at the proximal end of the image
guide 30. Alternatively, a video relay lens may be used to produce
an image directly onto a video camera. It is possible to use an
inexpensive CMOS camera, such as those used in cell phone cameras,
to produce an image that can be viewed on a video monitor. Further,
if a camera is used, a wireless transmitter may be deployed to
transfer the image to a remote receiver attached to a video
monitor. It is also possible to use the endoscopic camera that will
eventually be attached to the general endoscope (such as a
laparoscope) to produce the image that can be viewed on the main
video monitor or monitors in the operating room. The camera is
simply moved from the insufflation endoscope 10 to the general
endoscope after the insufflation endoscope 10 is no longer needed
for insufflation. A DIN standard eyepiece shape can be used to
facilitate the use of the endoscope camera for both
applications.
One possible embodiment of an optical system 60 is shown in FIG. 7.
The optical system 60 includes a beamsplitter prism 62 having a
first surface 64 in contact with the proximal end of the image
guide 30 (the knob 52 is not shown in FIG. 7 for convenience). The
beamsplitter prism 62 has a second surface 66, ideally disposed at
a 45-degree angle to the first surface 64, which is optimally
provided with a partially-silvered or partially-aluminized coating
having the property wherein some incident light is reflected and
some incident light is transmitted. Such coatings are well known in
the industry. Additionally, some beamsplitter coatings are designed
so that one polarization is reflected from and the other
polarization is transmitted through the coating. Such coatings may
be more efficient than partially-silvered or partially-aluminized
coatings because they absorb less light. These coatings are also
well known in the industry.
The optical system 60 further includes a light source 68, such as a
light emitting diode (LED) or LED array, located adjacent to the
third surface 70 of the beamsplitter prism 62. Light produced by
the light source 68 enters the beamsplitter prism 62, and at least
some of this light reflects off the second surface 66 and is
transmitted through the image guide 30 and the image conduit 20 to
illuminate the surface in contact with the distal tip 26. A light
trap (not shown) comprising a light absorbing media such as black
paint or black velvet is preferably located adjacent to the
beamsplitter prism 62, opposite the light source 68. Thus, any
light from the light source 68 that is transmitted through the
second surface 66 will impinge upon the light trap and be absorbed,
thereby reducing glare. An image of the illuminated surface in
contact with the distal tip 26 of the image conduit 20 is
transmitted back through the image conduit 20 and the image guide
30. This light enters the beamsplitter prism 62 and is at least
partially transmitted through the second surface 66. A lens 72
(which can be a compound lens, as shown, or a simple lens,
depending on the application) is located adjacent to the third
surface 66 to receive light transmitted through the
beamsplitter.
As discussed above, the lens 72 could be an ocular, through which a
surgeon could view the image of the surface in contact with the
distal tip 26, or the lens 72 could be a video relay lens to enable
the image to be displayed on a video monitor. In the illustrated
embodiment, the lens 72 focuses the image onto a "smart sensor" 74
that automatically detects when the distal tip 26 breaks through
the tissue and into the body cavity. When the distal tip 26 breaks
through the tissue and into the body cavity, there will be a
dramatic change in color and/or intensity of the image being
transmitted. By detecting this change in color and/or intensity,
the smart sensor 74 is able to determine when the distal tip 26
breaks through the tissue and into the body cavity. The smart
sensor 74 can include a light detector 76 which is arranged in line
with the lens 72 to receive the image projected through the lens
72. The light detector 76 produces a signal corresponding to the
intensity and/or color of the image. The signal produced by the
light detector 76 is provided to a logic circuit 78, and when the
signal changes dramatically, the logic circuit 78 produces an
output signal indicating that the distal tip 26 has broken through
the tissue and into the body cavity. It should be noted that the
smart sensor 74 could be used in conjunction with either an ocular
and/or a video relay lens.
Preferably, the space between the light source 68 and the third
surface 70 is filled with an index matching clear adhesive 74 to
reduce Fresnel reflections. Thus, all air-to-solid (e.g.,
air-to-silica or air-to-glass or air-to-plastic) interfaces along
the entire optical path (i.e., from the distal tip 26 to the light
source 68) are substantially eliminated. Additionally, because the
object being viewed is in contact with the distal tip 26, the
reflective interface at the tip is also substantially eliminated.
Therefore, the endoscope 10 can successfully utilize
"through-the-lens" illumination without washing out the image with
extraneous reflections. As a possible alternative, illumination may
be by conventional optical fibers, as is well known in the art for
providing endoscopic illumination. If conventional optical fibers
are used, lighting of the field of view is accomplished by
transillumination. Transillumination is the scattering of light
from the vicinity of the field of view to the actual field of view
by scattering within the tissue itself.
When using the endoscope 10, a surgeon is able to visually monitor
the making of an initial incision by observing the image output by
the optical system 60. This enables the surgeon to precisely and
safely position the tip of the endoscope 10 into the body cavity.
If it is desired to insufflate the body cavity, the image guide 30
is removed once the tip of the endoscope 10 is properly positioned
in the body cavity. The valve 58 is then opened to allow gas from
the gas source to flow into the now hollow interior of the
endoscope 10 and into the body cavity through the insufflation
channel 28 to insufflate the body cavity.
While specific embodiments of the present invention have been
described, it should be noted that various modifications thereto
could be made without departing from the spirit and scope of the
invention as defined in the appended claims.
* * * * *